~ Query 11. lis duration ?» He Te aay a 
Answer. When it throws up. geritle and moiterdte 
crops, its efficacy is of the longest duration. If it is vio- 
lent in its first operation, it is of short continuance. I 
have known it exhaust itselfin one year. But I have 
had benefit from one dressing of three or four bushels 
to the acre, for five or six years; gradually decreasing 
in its powers. I prolong the efficiency of dung, by 
plaistering the second or third, vear, when the clover, 
on dunged or any other ground, begins to fail. Perhaps. 
the scattering it annually, or every other year, in‘small 
portions, will continue for a length of time gentle ope- 
rations, and prevent violent efforts. I have heard of 
some who have practised sowing it frequently, and m 
small quantities, and obtained good crops of grass for 
twelve years and upwards. ) 
The weedsof our fields, (/) which have beenat former 
periods under bad culture, forbid their laying in grass, 
(h) The Fapanese, as well as the Chinese, reject the dung of 
horses and cattle, because they contain the seeds of weeds, and 
use night soil, which their laws compel them to save. “ Their 
fields are for this reason, (among others) so free from weeds, 
that a celebrated botanist, passing lately through Japan, with 
the Dutch embassy, could scarcely find any other plants 
on the corn fields, but the corn itself.” Ingenhausz food of 
plants, page 15. If what has been quoted on this subject will 
have no other effect on our practice, it ought to warn us to 
be more careful in rotting or composting our dung of horses, 
&c. and to prevent the seeds of weeds mixing w ith our manure. 
Nothing in this country is in so miserable a stile as the mis- 
management (with some exceptions) of our stercoraries. The 
wi . 
ae: 
